AGENDA REQUEST

Sponsor:

Board of Supervisors Meeting Date:

Staff Lead:

Department:

Topic:

An Ordinance
to Amend Subsection 3 of Section 204.2 of the Design
Standards Manual to Limit Its Application to Point Source
Stormwater Runoff

Topic
Description:

Section 204.2 of the Design Standards Manual (DSM) provides
a general policy for water quality in stormwater management
(SWM) and Best Management Practices (BMP) facilities.
Subsection 3 requires the adequate treatment of stormwater
runoff generated from new development sites prior to
discharge into a jurisdictional wetland or local water
body. This proposed amendment specifies that the provision
is intended to apply to point source discharges of
stormwater and not from non-point source runoff, such as
dispersed sheet flow from residential lawns.

Requested Action of the Board of Supervisors:

Consider one
of the following options:

Adopt
the ordinance as originally drafted to specify that
Subsection 3 applies to point source discharges of stormwater. Delete the amendment regarding tree
conservation easements that was added at the November 8,
2007 meeting;

Retain
the existing language of Subsection 3 to apply to both
point and non-point discharges of stormwater and add
language to clarify that natural vegetative areas within
tree conservation easements with a maximum slope of 5%
are considered a method of adequate treatment for the
sheet flow of stormwater.

Financial Impact Analysis:

There is no financial impact.

Summary Staff Report:

Subsection 3
of Section 204.2 provides that all stormwater generated by
new development shall not be discharged into a
jurisdictional wetland or local water body without adequate
treatment. The standard for adequate treatment has been the
use of a vegetative filter strip of about 25 feet in width
to filter out pollutants and particulate matter prior to the
water entering the wetland or water body. A similar
provision was part of the draft Virginia Stormwater
Management Model Ordinance at the time the County adopted
its Stormwater Management Ordinance (and this provision) in
2002. The Stormwater Management Ordinance was subsequently
incorporated into an overall Design Standards Manual. The
State eliminated this provision from the Virginia Stormwater
Management Law when it was adopted in 2005. The Army Corps
of Engineers and the Department of Environmental Quality (DEQ)
have oversight related to impacts to wetlands and water
bodies. The DEQ Virginia Water Protection individual
permits’ Standard Project Conditions have a clause in them
that requires pretreatment of surface water runoff prior to
entering into regulated wetland areas. (A DEQ staff member
has indicated that they have contemplated removing this
language from their standard permit conditions because they
feel “this sort of stormwater management is a local issue
that should be handled by localities.” (email from Allison
C. Dunaway, Virginia Water Permit and Regulatory Team
Leader, DEQ, June 6, 2007))

Since
adoption of this provision in 2002, it has been interpreted
as including both point source and non-point source
discharges into wetlands. The non-point sources are
primarily lawns and yards associated with residential
development. This has shown to be problematic for
residential projects, such as Brookside, where there are a
considerable amount of wetlands and they have already paid
for or mitigated their impacts to the wetlands in accordance
with their Corps of Engineers permit. In the application of
this provision, the County has encouraged and stressed the
importance of preserving existing vegetation as filter
strips for non-point source treatment as long as the
topography is relatively flat (less than 5% slope) to
maintain sheet flow conditions as opposed to disturbing the
land and increasing the potential of sediment eroding into
the wetlands.

This amendment proposes to specify the requirement for
adequate treatment for point source discharges. Having
pretreatment of stormwater runoff prior to being discharged
into jurisdictional wetlands is a good practice because it
helps to preserve the overall health of the ecosystem as
well as the vibrancy of the wetlands. To overload them with
concentrated pollutants suspended in stormwater runoff that
will primarily be collected from roadway areas and/or other
impervious areas would contribute to the wetlands premature
degradation and possible destruction. In addition,
pretreatment will allow for screening out trash, debris, and
other large material, as well as for initial filtering of
other smaller suspended particulate matter in the runoff
that over time will eventually choke the wetlands ability to
thrive.

The addition of the point source language in our Design
Standards Manual reinforces the importance of pretreatment
in the preservation and protection of these wetland areas.

Updated Information:

The Board of Supervisors held a public hearing on this
amendment to the Design Standards Manual at their November
8, 2007 meeting. At that time, a change was made to the
draft ordinance to specifically clarify that a tree
conservation easement is considered a method of adequate
treatment for the discharge of stormwater into a wetland.
In follow-up discussion with Engineering, it was found that
the maintenance of natural vegetation in tree conservation
easements works well as a filter for the sheet flow of
stormwater (non-point source) but does not work for point
source discharges unless that discharge is reduced to sheet
flow (with a level spreader or similar mechanism) prior to
its discharge. It is recommended that the change made at
the November 8 meeting be deleted if the provision is
adopted to apply only to point source discharge.

There was considerable discussion about whether the overall
provision for pretreatment was in concert with the Virginia
Stormwater Management Law and what other laws regulate the
pretreatment of stormwater prior to discharge into
jurisdictional waters. Staff has conducted some research
into this issue and offers the following information to
assist the Board’s in its deliberation of this proposed
amendment.

Current County Practice: In the review of
development projects, the County’s practice has been to
interpret Subsection 3 of Section 204.2 to apply to the
discharge of all stormwater, both piped and sheet flow from
adjoining property, whether the adjoining land is developed
as a parking lot or as residential yard areas, into
jurisdictional wetlands or water bodies. It has been
applied in all instances within a development site as well
as with water leaving a development site. (Applying the
requirements within a development site has been
raised by some as more restrictive than the State
requirements. 4VAC50-60-50.H. reads in part, “Proposed
residential, commercial or industrial subdivisions shall
apply these stormwater management criteria to the land
disturbance as a whole. Individual lots in new subdivisions
shall not be considered separate land-disturbing activities,
but rather the entire subdivision shall be considered a
single land development project.”)

In 1982, the County endorsed the goals of the Occoquan Basin
Non-Point (meaning stormwater) Pollution Management Program
to maintain “acceptable levels of water quality within the
Occoquan Basin’s free-flowing streams and impoundments”
through the application of stormwater quality BMPs. Over
time, the Board has encouraged stormwater management,
recognizing the community’s sensitivity to Fauquier County’s
location at the headwaters of both the Rappahannock and the
Occoquan. With the adoption of the stormwater management
ordinance in 2002 (and the DSM in 2005), the Northern
Virginia BMP Handbook was designated as the authority for
the design and review of BMP facilities using the Occoquan
Method. The Occoquan Method is performance-based and
offers more flexibility than that required under strict
compliance with State SWM requirements.
The State approved our use of the Occoquan Method in
their review of our SWM ordinance prior to its adoption.
The basic principle is that SWM/BMPs are required for at
least 80% of a development site (with up to 20% of the
stormwater allowed to bypass and not be treated). A minimum
of 40% of the calculated phosphorus for the entire site must
be removed through the use of sediment forebays,
bioretention facilities, filter strips and other BMP
measures. (A credit is given for floodplain and wetland
areas.) A project must meet this removal rate at the point
of discharge from the project site. In some cases, water
from the wetlands will flow into the SWM facility, thus the
adequate treatment prior to discharge into the wetland may
actually be a pretreatment. In other instances, generally
with the sheet flow from yard areas, this water is not
captured in the SWM/BMP facility and is part of the 20%
bypass water. Thus, the use of pretreatment for this bypass
water prior to entering the wetland may actually result in a
somewhat higher level of phosphorus removal than the minimum
40% required. It is also a means to help ensure the health
of the wetland and to improve water quality within the site,
not just as the water leaves the site.

Federal
Requirements: Section 404 of the Clean Water Act (CWA),
as amended, established a permit program that deals with the
placement of dredged or fill materials into wetlands and
other "waters of the United States." The 404 permit
program is administered jointly by EPA and the U.S. Army
Corps of Engineers.

The Corps
handles the actual issuance of permits (both individual and
general); it also determines whether a particular plot of
land is a wetland or water of the United States. The Corps
has primary responsibility for ensuring compliance with
permit conditions, although EPA also plays a role in
compliance and enforcement.

Among the
many issues reviewed and analysis needed as part of the
issuance of any wetlands disturbance permit is the
evaluation of the suspended particulates/turbidity for the
possible loss of environmental characteristics and values
that can result from greatly elevated levels of suspended
particulates in the water.

In addition,
Section 401 of the CWA requires that before a federal agency
can issue a license or permit for construction or other
activity, it must have received from the state in which the
activity will take place a written certification that the
activity will not cause or contribute to a violation of
relevant state water quality standards (see VSMP below).

The CWA
makes it illegal to discharge pollutants from a point source
(and discharges from construction sites disturbing over one
acre are considered in this classification) to the waters of
the United States. Section 402 of the Act creates the
National Pollutant Discharge Elimination System (NPDES)
regulatory program. Point sources must obtain a discharge
permit from the proper authority (in our case, the Virginia
Department of Conservation and Recreation).

Though the
CWA does contain a long-range goal of zero discharge of
pollutants, these permits do not, as the name of this
program might suggest, simply say "no discharge." Rather,
they set limits on the amount of various pollutants that a
source can discharge in a given time.

Where wetland impacts occur, the Department of Community
Development asks for proof of wetlands disturbance permits
from the Corps of Engineers and the Department of
Environmental Quality (DEQ) and typically requests copies of
the permits issued. One of the Standard Project Conditions
of the DEQ Individual Permit states: “Untreated stormwater
runoff shall be prohibited from directly discharging into
any surface waters. In accordance with the Virginia Erosion
and Sediment Control Handbook, Third Edition, 1992,
appropriate best management practices (BMP) shall be deemed
suitable treatment prior to discharge into surface waters.”

State Permitting: For compliance with the CWA, the
Commonwealth requires a Virginia Stormwater Management Plan
permit (VSMP) for development sites greater than one acre in
size. This permit is administered through the Department of
Conservation and Recreation (DCR). The County requires
evidence of application for this permit prior to the
issuance of a land disturbing permit for every project
requiring a VSMP permit. This is a general permit, which by
execution of the application (Notice of Intent to Comply)
the developer agrees to comply with a series of general
conditions, including the preparation of a Stormwater
Pollution Prevention Plan (SWPPP) in accordance with defined
standards. The SWPPP is not a reviewed plan, but one to
which DCR may require modifications to comply with the VSMP
permit during construction of the project. DCR spot checks
construction sites and may shut down a project for failure
to have a copy of the SWPPP available or to follow the SWPPP
on site. Most of the provisions of the SWPPP deal with the
construction activity; however, there are specific criteria
required in the preparation of the SWPPP that address the
control of pollutants in stormwater discharges after
construction operations have been completed, including the
technical basis used to select the practices to control
pollution and flows that exceed predevelopment conditions.

Practice of Other Jurisdictions: Staff has surveyed
several other jurisdictions in the area (Stafford,
Albemarle, Spotsylvania and Loudoun counties) about their
requirements and practices for pretreatment within the site
prior to the main SWM/BMP facility (and discharge from the
site).

Albemarle: Albemarle County’s requirements are
actually more stringent than the State guidelines. The
Albemarle County Code states, “If the development is
located within a development area or an area of infill and
redevelopment, stream buffers shall be retained if present
and established where they do not exist on any lands subject
to this article containing perennial streams, and/or
nontidal wetlands contiguous to these streams. The stream
buffer shall be no less than one hundred (100) feet wide on
each side of such perennial streams and contiguous nontidal
wetlands, measured horizontally from the edge of the
nontidal wetlands, or the top of the stream bank if no
wetlands exist.” (Section 17-317 (A)) In essence, they
require a 100-foot vegetative buffer along jurisdictional
wetlands and water bodies.

Loudoun: Loudoun County has a less restrictive
provision within their Facilities Standards Manual, which
states: “Discharge of stormwater pollutants to wetlands
shall be minimized, except where constructed wetlands are
used as a BMP and are designed in accordance with County
Standards.” (Section 5.310 F) In practice, Loudoun
County is more laissez-faire and applies this provision to
the point discharge of stormwater into wetlands, with the
focus more on reducing potential erosion before entering the
wetland not on improving water quality. They have indicated
that they have not been consistent in its application.

Spotsylvania and Stafford: Both Spotsylvania and
Stafford counties have the same practice with regard to
discharges into wetlands and are being discussed together.
Neither county enacted the language from DCR’s Model
Ordinance but both utilize the performance criteria of the
Chesapeake Bay Preservation Area Designation and Management
Regulations, which requires treating stormwater runoff prior
to discharging into wetlands located offsite. It
does not, however, ensure treatment of all stormwater runoff
prior to discharging into wetlands located within the
project site.

In recent years, both counties (along with the City of
Fredericksburg) have developed a policy document with
strategies to improve existing subdivision and regulations
to benefit both the natural environment and the community.
One of the principles (#22) of the document states, “New
stormwater outfalls should not discharge untreated or
unmanaged stormwater into jurisdictional wetlands,
sole-source aquifers, or other water bodies.”

Stafford and Spotsylvania counties are currently working on
revisions to their stormwater management regulations as a
result of EPA push on the State for more stringent
regulations to improve the water quality of the Chesapeake
Bay knowing it will eventually become the responsibility of
the local level. In their new regulations, they expect to
be applying principle #22 above to point source discharges
only, but applying it for all discharge into wetlands, both
within the site and as water leaves the site.

Additionally, DCR is currently exploring new regulations to
increase the required removal rates for phosphorus, nitrogen
and suspended solids in stormwater to help improve water
quality in the Chesapeake Bay. The most recent evaluation
of the health of the Chesapeake Bay was released this week
and, according to an article in the Washington Post, the
bay’s pollution has actually taken a turn for the worst.
The recent study, conducted by the U.S. Geological Survey,
shows increases in the amount of phosphorus and nitrogen,
which help fuel the large algae blooms that create dead
zones in the bay.